Classius de Oliveira

• Abstract

  Anurans have pigment cells (melanocytes and melanomacrophages) in different organs and membranes, which have melanin. The visceral pigmentation can be related to residual melanin accumulation, may have a role in the immune system, antioxidant functions, and protect the tissue. One of the objectives of this study is to describe the morphometric characteristics of the hepatic melanomacropha…

  The liver of anuran amphibians: morphology compared between 10 species and action of benzopyrene in the melanomacrophages of Physalaemus cuvieri, AP.R

• Abstract

  Amphibians and fish have in addition to colorful skin also pigment cells (melanocytes and melanomacrophages) in different organs and membranes, which have melanin. This visceral pigmentation can be related to residual melanin accumulation, may have a role in the immune system, antioxidant functions, and protect the tissue against DNA damage. The objectives of this study are to test the fu…

  The influence of environmental contaminants (cyproterone acetate and nonylphenol) and abiotic factors (temperature and UV radiation) in the internal Melanin in anurans, AP.R

• Abstract

  We expect to detect and describe the effects of the herbicide formulated glyphosate and atrazine for larvae Eupemphix nattereri (Leiuperidae) and Rhinella schneideri (Bufonidae). Using appropriate experimental designs we want to have information to evaluate and prove the toxicity of products (environmental contaminants / endocrine disruptors) as used in our region (northwest of São Paulo)…

  Toxic effects of the herbicides Atrazine and Roundup in Eupemphix nattereri (Leiuperidae) and Rhinella schneideri (Bufonidae): morphological changes under different concentrations and abiotic conditions (pH, temperature and photoperiod), AP.R

(Only some records are available in English at this moment)

• Pigment composition of hepatic melanomacrophages in 15 species of anurans, BP.TT

• Abstract

  Anurans are vulnerable to various pollutants. Benzo[alpha]pyrene (BaP) is a contaminant with hepatotoxic, immunotoxic and genotoxic properties. Metabolized by the enzyme P450 (CYP1A1) produces toxic subproducts that can lead to the death of organisms. However, defense cells aid in the detoxification process. Melanomacrophages (MMs) are phagocytic cells that produce melanin, and the melani…

  Morphofunctional changes in hepatic melanomacrophages of Physalaemus cuvieri (Anura: Leptodactylidae) induced by the contaminant benzo[alpha]pyrene., BP.DR

• Abstract

  The anurans have an extracutaneous pigmentary system, composed of melanocytes, which have an intense pigmentation and are responsible for the melanin's synthesis, and melanomacrophages, with phagocytic activity. These pigments are found in liver, spleen, kidneys, peritoneum, lungs, heart, blood vessels, thymus, gonads and meninges. The pigmentary system can be changed due to environmental…

  Analysis of the extracutaneous pigmentation of two populations of Physalaemus cuvieri (Anura: Leptodactylidae) and its correlation with abiotic factors, BP.IC

(Only some records are available in English at this moment)

• Abstract

  Benzo[a]pyrene (BaP) is a toxic compound present in the environment and capable to affect fish and amphibians. The liver of these vertebrates have cells with detoxification function called melanomacrophages (MMs). A characteristic of MMs is the capacity of produce and store melanin, a protection pigment that is able to eliminate free radicals and neutralizing cations, thereby protecting t…

  Effects of benzo[a]pyrene on the cytoskeleton and melanin dispersion of hepatic melanomacrophages of fish and amphibians, BE.EP.DR